Improve parent process check in CEFLauncher

Author: botder

Client/ceflauncher_DLL/Main.cpp

@@ -9,8 +9,13 @@
  *
  *****************************************************************************/
 
+#define WIN32_NO_STATUS
 #define WIN32_LEAN_AND_MEAN
 #include <Windows.h>
+#undef WIN32_NO_STATUS
+#include <ntstatus.h>
+#include <winnt.h>
+#include <winternl.h>
 #include <delayimp.h>
 #include "CCefApp.h"
 #include <string>
@@ -21,6 +26,8 @@
     #pragma comment(lib, "cef_sandbox.lib")
 #endif
 
+DWORD WINAPI CheckParentProcessAliveness(LPVOID);
+
 int _declspec(dllexport) InitCEF()
 {
     // Get absolute CEFLauncher.exe path
@@ -46,20 +53,62 @@ int _declspec(dllexport) InitCEF()
     sandboxInfo = scopedSandbox.sandbox_info();
 #endif
 
-    if (HANDLE job = CreateJobObjectW(nullptr, nullptr); job != nullptr)
+    const HANDLE parentCheckThread = CreateThread(nullptr, 0, CheckParentProcessAliveness, nullptr, 0, nullptr);
+
+    const int exitCode = CefExecuteProcess(mainArgs, app, sandboxInfo);
+
+    if (parentCheckThread != nullptr)
     {
-        JOBOBJECT_EXTENDED_LIMIT_INFORMATION limits{};
-        limits.BasicLimitInformation.LimitFlags = JOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSE;
+        TerminateThread(parentCheckThread, 0);
+        CloseHandle(parentCheckThread);
+    }
 
-        if (SetInformationJobObject(job, JobObjectExtendedLimitInformation, &limits, sizeof(limits)))
-        {
-            AssignProcessToJobObject(job, GetCurrentProcess());
-        }
-        else
+    return exitCode;
+}
+
+static DWORD WINAPI CheckParentProcessAliveness(LPVOID)
+{
+    NTSTATUS(NTAPI * queryInformation)(HANDLE, PROCESSINFOCLASS, PVOID, ULONG, PULONG) = nullptr;
+
+    if (HMODULE const ntdll = GetModuleHandleW(L"ntdll.dll"); ntdll != nullptr)
+    {
+        queryInformation = reinterpret_cast<decltype(queryInformation)>(GetProcAddress(ntdll, "NtQueryInformationProcess"));
+    }
+
+    if (queryInformation == nullptr)
+        return 1;
+
+    PROCESS_BASIC_INFORMATION info{};
+
+    ULONG    returnLength = 0;
+    NTSTATUS status = queryInformation(GetCurrentProcess(), ProcessBasicInformation, &info, sizeof(info), &returnLength);
+
+    if (!NT_SUCCESS(status) || returnLength < sizeof(PROCESS_BASIC_INFORMATION))
+        return 2;
+
+    const auto   parentProcessId = static_cast<DWORD>(reinterpret_cast<ULONG_PTR>(info.Reserved3));
+    const HANDLE parentProcess = OpenProcess(SYNCHRONIZE | PROCESS_QUERY_LIMITED_INFORMATION, FALSE, parentProcessId);
+
+    if (parentProcess == nullptr)
+    {
+        if (GetLastError() == ERROR_INVALID_PARAMETER)
+            ExitProcess(0);
+
+        return 3;
+    }
+
+    while (true)
+    {
+        DWORD exitCode{};
+
+        if (!GetExitCodeProcess(parentProcess, &exitCode) || exitCode != STILL_ACTIVE)
         {
-            CloseHandle(job);
+            CloseHandle(parentProcess);
+            ExitProcess(exitCode);
         }
+
+        Sleep(1000);
     }
 
-    return CefExecuteProcess(mainArgs, app, sandboxInfo);
+    return 0;
 }